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Finding the Fourth Proportional to 643.72, 888.19 and 434.29

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Solution

The fourth proportional to 643.72, 888.19 and 434.29 is: 599.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.72 : 888.19 = 434.29 : x
  2. Step 2: Convert to fraction form
    643.72/888.19 = 434.29/x
  3. Step 3: Cross multiply
    643.72x = 888.19 × 434.29
  4. Step 4: Simplify right side
    643.72x = 385,725.42
  5. Step 5: Solve for x
    x = 385,725.42/643.72
  6. Step 6: Final answer
    x = 599.21

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.